<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../js/jquery-1.11.3.js"></script>
</head>
<body>
<a href="http://www.baidu.com" title="baidu" alt="little" name="notgood">aaa</a>
<a href="http://www.sohu.com">aaa</a>
<script>
    var s = $('a').attr('target','_blank').attr('rel','nofollow')
    var s2 = $('a').removeAttr('target').removeAttr('target')

</script>
</body>
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